This invention relates to an impact system for use, for example, in evacuation of occupants from burning buildings and the like. More particularly, this invention relates to a system for the purposes described including an inflatable member for safely breaking the fall of a person jumping from the building to escape therefrom.
Emergency escape of evacuees from multi-story buildings which are burning or subject to a like hazard so as to prohibit ordinary egress from the building has heretofore been accomplished by means such as extension ladders, hand-held safety nets, chutes, fire escapes and inflatable cushions. With the exception of the safety net, the aforementioned emergency escape devices are constrained in their utility by limited portability. Even a safety net, while fairly portable, requires the involvement of skilled, trained personnel. In regard to impact systems using inflatable cushions, the prior art systems have limited portability due to the need for a power driven inflation source for initial deployment and replenishment of air vented upon impact to soften said impact. In the prior art devices, an electric motor driven blower is typically used as the inflation source, and as the makeup gas supply for gas that is vented to the atmosphere through relief valves for dissipating impact energy. In an arrangement of this type, not only is portability sacrificed, but the capability to rapidly accept evacuees is restricted by the need to reinflate the system to its operating pressure each time impact is achieved so that it will be ready for the next evacuee.
The present inventor is aware of the following prior art relating generally to the subject matter of the invention: U.S. Pat. No. 2,390,955 (Dec. 11, 1945); U.S. Pat. 2,797,853 (Jul. 2, 1957); U.S. Pat. No. 2,906,366 (Sep. 29, 1959); U.S. Pat. No. 3,310,818 (Mar. 28, 1967); U.S. Pat. No. 3,391,414 (Jul. 9, 1968); U.S. Pat. No. 3,399,407 (Sep. 3, 1968); U.S. Pat. No. 3,840,922 (Oct. 15, 1974); and U.S. Pat. No. 3,851,730 (Dec. 3, 1974).
U.S. Pat. No. 2,390,955 relates to a fire escape system including an inflatable bag that can be quickly expanded or inflated by use of a high volume of low pressure air such as may be available from standard fire equipment. The requirement for auxiliary equipment restricts the use of the patented system.
U.S. Pat. No. 2,797,853 relates to an inflatable safety bag or the like wherein the compressed air that fills the bag and absorbs the impact energy is allowed to escape through relief valves so as to avoid the tendency to resist the force of the falling body causing the body to be thrown from the bag with possible resultant injury. In an arrangement of this type, the bag must be reinflated for subsequent use and hence cannot rapidly accept evacuees or the like.
U.S. Pat. No. 2,906,366 is directed to an inflatable member including an arrangement for gradually absorbing the impact of a body landing on the bag and thus relates to a different structural arrangement than that of the present invention.
U.S. Pat. No. 3,310,818 relates to an inflatable shock absorbing mat including a plurality of superimposed inflatable chambers and a plurality of manifolds around the sides of said chambers. An object impacting the top of the mat forces air from the superimposed chambers through air passages into the manifolds, and then through exhaust valve outlet means to the atmosphere whereby the constriction of air flow through said air passages provides a shock absorbing effect for a falling object impacting the mat. Here again, reinflation of the apparatus is necessary for successive impact situations which limits the use of the arrangement.
U.S. Pat. No. 3,391,414 relates to a pneumatic landing pit cushion constructed so as to embody a relatively stiff though yieldable rim portion and a softer more highly yieldable central cushioning portion, thereby tending to deflect a body upon impact inwardly into the cushioning area, rather than outwardly over the periphery of the cushion in the event of a landing near the periphery. The arrangement tends to minimize the likelihood of injury resulting from deflection of the cushion unto the hard supporting surface surrounding the cushion. The patented device relates to a different structural arrangement than that of the invention disclosed herein.
U.S. Pat. No. 3,399,407 relates to a cushion for decelerating falling bodies and features a closed flexible bag having a conduit communicating with the bag and a continuously operating fan unit in the conduit for creating artificial currents of air to maintain the pressure in the bag at a predetermined level. Air expelled from the bag upon impact of a falling object flows in a reverse direction through the fan unit to avoid pressure buildup sufficient to damage the object. This invention requires an independent fan unit for inflation purposes, the same being advantageously avoided by the arrangement of the invention herein disclosed.
U.S. Pat. No. 3,840,922 relates to a landing cushion for falling objects featuring a relatively high pressure cushion in advance of a lower pressure cushion to widen the impact area of the falling object on the lower pressure cushion, thus distributing the force of the object over a larger area and allowing the decelerating inflation pressure to be relatively low at the moment of impact. This is seen to be a different structural arrangement than that of the invention herein disclosed.
U.S. Pat. No. 3,851,730 teaches an inflatable safety cushion wherein an inflatable section defines a generally closed air system and an air breather system is located in said section for allowing air to be rapidly exhausted from the interior of said section upon impact of a body falling thereon. The breather system is arranged to allow quick but controlled release of built-up air pressure upon impact of an object. With an arrangement of the type described the safety cushion is not readily available for subsequent impact situations as is the present invention.